The case of the fungus is a further example of the greater forwardness of the plants in the north.
There can be no doubt that the characteristics of the east coast vegetation are due to the prevalence of cold winds and the occurrence of cold currents.
Whilst crossing the island several interesting features of the vegetation were noticed. Between Akureyri and our first camp (Thverá) several "forests" were passed through, consisting of Betula nana, Vaccinium uliginosum, and Willows, Salix lanata and S. glauca rising to a height of from nine to eighteen inches, with an undergrowth of other small plants.
The hillsides all round were covered by Dryas octopetala, which was by far the commonest plant in the northern half of the island, and it was abundant also on the east coast.
Travelling along the Oxnadal and then turning off towards Silfrastathir, Dryas at first was the most conspicuous feature of the vegetation covering the rocky moraines and talus slopes; but about three miles from the head of the valley the Dryas was replaced by Cerastium alpinum and Potentilla maculata, which then in their turn became the dominant plants for a considerable distance. As we traversed the island we kept passing through well-marked zones of different plants, whose limits seemed largely to be determined by the character of the soil.
After crossing the "col" some very rough screes were passed, on which the Iceland poppy, P. nudicaule, was growing abundantly. The screes were formed of rough angular blocks with very little soil between them, and the poppy was only growing in the most barren spots; where moraines occurred the poppy did not grow. It was also found on the stony ground by the river at Silfrastathir.
The hillsides were covered in many places by large tracts of Equisetum (E. arvense and E. pratense). The various species of the Equisetaceæ seem to be among some of the commonest plants of the island. The swampy regions by the rivers are covered with Equisetum and Scirpus cæspitosus; and they are very abundant on the mountains.
From the river until we reached Gilhagi, the flora showed no features of any particular note; but a meadow there with large plants of Saxifraga cernua in full flower was a very beautiful sight.
On ascending from Gilhagi a change in the flora was gradually seen. After about 2000 feet Pedicularis flammea appeared and became common; on the lower slopes the leaves were green and the plants tall, but at greater elevations the plants became short and stunted, with deep red leaves. The high ground was very much broken up, being of a deep hummocky character and covered by a dwarfed growth of Willows, Empetrum, Mosses, etc.
Passing over ground from which the snow had just melted, the willows were found to be either still quite bare or just coming out into leaf, but everywhere in such barren places cones of Equisetum were seen sticking up on pale brown stalks some six inches above the soil; the sterile green shoots do not grow up until some time after the appearance of the cones.